Sewing mechanism



May 23 1-939.

T. H. DE SPAIN SEWING MECHANISM Filed May 17, 1938 11 Sheets-Sheet 1 HisWoman 1s May 23, 1939. T. H. DE SPAIN 2,159,688

SEWING MECHANISM y 23, 939- v THHDESPAIN 2 159,688

SEWING 'MEGHAN/I SM Filed May 17. 1938 11 Sheets-Sheet I5 'IHHHH Thom H3LS Q IL,

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T. H. DE SPAIN SEWING MECHANISM Filed May 17, 1 938 t 11 Sheets-Sheet 4May 23, 1939.

T. H. DE SPAIN SEWING MECHANISM Fi le d ma 17, 1958 11 Sheets-Sheet 5mamas Hfie S am/'71,,

3H5 abbowws T: H. be SPAIN 2,159,688

SEWING MECHANISM May 23, 1939.

Filed May 1'7, 1938 ll Sheets-Sheet 6 May 23, 1939. T. H. DE SPAINSEWING MEcfiANIsM Filed May 17, 1938 ll Sheets-Sheet 9 Tkoinasfiflelfi'pam Wis 6mm May 23, 1939.

' T. H. DE SPAIN SEWING MECHANISM Filed May 17, 1938 ll Sheets-Sheet 10Thomas H fie pal/ suls Wm.

May 23, ,1939. 'r. HIDE SPAIN 2,159,683

* SEWING MECHANISM I Filed May'l'f, 1938 11 Sheets-Sheet 11 Thomas Hfie86 y *9 T w PatentedMay 23, 1939 'umTsosTAT- s PATENT QFFIGE SEWINGMECHANISM Thomas ,H. .De Spain, Paducah, Ky., assignor to SouthernTextile Machinery Company, Padilcah, Ky., a corporation of Kentuc lgyApplication .May 17, 1938, Serial No. 208,465 reclaims. (01. 112-25)ingmachines and, particularly, to machines com- 1 mainly referred to as.dial loopers generally used i 5a, rials. i

,Priinarily, the object of the invention is to provide a sewingmechanism for a machine of ,this type adapted for use in connection withunit a ing fabric materials. Briefly, these machines 1 lpacompriseaseries of work-supporting elements, known as work pointausually carriedon a contlnuously revolving dial so that the points are successivelymoved past the thread-carrying needles of the sewing mechanism; Theloops ofyarn or other thread, of. which the materials for unitingsections or pieces of knitted mate- ;called work points and, asthepoints successively hethread-carryin-g needles,-of ,which there '20 g'hthe workloops on the points from opposite sides of the work loops. Oneneedle is retracted while the other is advanced and,as each needle isadvanced through the work, locpei' devices form a loop in the thread ofthe advanced needle. At this time, the other needle is in f retractedposition and is then advancedthrough I j the thread loop beforepenetrating the work. As

will be appreciated, where comparatively finemeshedgoods are beingunited, the work points 1 30': must necessarily be positioned very closeto one another and, in addition, they must be comparal tWelythin so thatthe needles of the sewing mechanism are also necessarily of small cross-3 section+so much so that they are exceedingly 35- flexible. As aresult, means must be provided for forming loops in the needle threadsin such fashion as to be certain not to flex the needles or, otherwise,the needles will not register with the work-supporting points, acondition that 40 must be maintained because of the fact that the Thisinvention relates to improvements in sewwork points are constantlymoving, as distinguished from an intermittent movement, and it is iabsolutely necessary that the needles be alined 1 or? in registry withthe work points at all times i, 45 otherwise, the needle will not enterthe loops 1 of theknitted fabrics; on the work points. Specifically;therefore, another object of the inventionis to provide a novel form oflooper mecha- ;j Xnism capable of being used in conjunction with soneedles of exceedingly small cross-section, in l that the present loopermechanism will form the @necessary loops in the needle threads withoutdeflecting the needles so as to move the :latter 1 out ofproper-registry or alinement with the f ,55 work-loop-supporting points.1

toubeunitedare formed, are placed on these sotwofithe needles areadvancedand retracted As is also well known in the art to which thepresent invention relates, a number of pieces of work are usually on thework-point dial at the same time, the number of loops in, ,or the lengthof, each pair of mated pieces of material to be 5 united seldom, ifever, corresponding to that of the entire series of work points on thedial. Sue cessive pairs of mated pieces to be united are necessarilyspaced somewhat from each other, circumferentially of the dial, and itis necessary 1:0: to provide means for continuing the formation'ofnormal stitches during the operation of. the sewing mechanism while workpoints between pieces of work are passing thesewing mechanism. In

machines of theprior art of comparatively wide 15,

apart, it has generally been the practice to provide what are knownasiiacks in the form-o1 elements that are adapted to project up throughthe spaces between contiguous workpoints, so as to restrain or limit themovement of the needle threads as the needles are advanced or retractedpast the plane in which the work loops are normally positioned on thework points. This formation of stitches, in conjunction with the jacks,between successive pieces of work is what is known as chaining off, Theuse of these so-called jacks, however, is dependent upon the presence ofsufficient spaceto accommodate them between contiguous work points andanotherobject of the present invention isto providenovel means foreffecting this so-called chaining oil operation in machines of thepresent type having comparatively small, closely spaced work points foruse in connection withfine-meshed fabrics or, in other words, machinesin which the work points are so closely spaced as not to permit the use"of jacks for the chaining off operation. 0

More specifically, the invention contemplates the use of members which,forconvenience, will be termed chain stitch-fingers, rigidly or fixedlymounted, preferably above the work points, but offset downwardly to andslightly beyond the plane in which the needle threads are normallymovedby their respective needles. -Ihese chain stitch fingers-arelocated in positions where they will be at opposite sides of work loopsthat are on the points and will not interfere with the normal sewingoperations but, the absence of work loops on the work points, saidfingers will limit the movement of-the needle threads, substantiallyjust the same as would the work loops if theywere present and, thus,permit the continuous production of stitches in a chain-like formationuntil the next pieceof work is brought into operative relationship withrespect to the needles.

With these and other objects in view, the invention consists in certaindetails of construction and combinations and arrangements of parts, allas will hereinafter be more fully described, and the novel featuresthereof particularly pointed out in the appended claims.

In the accompanying drawings- Figure 1 is a top plan view of a diallooper machine embodying the present improvements, but with portions ofthe dial omitted;

Fig. 2 is a vertical sectional view on the line 22 of Fig. 1;

Fig. 3 is a view similar to Fig. 1, but showing, on a somewhat enlargedscale, the stitch fingers and the looper mechanism, including theoperating connections for the latter;

Fig. 4 is a vertical sectional view on the line 4-4 of Fig. 1; I

Fig. 5 is a detail horizontal sectional view on the line 5--5 of Fig. 4;

Fig. 6 is a vertical sectional View on the line 5-6 of Fi 1;

Fig. '7 is a detail perspective view of the two stitch fingers;

Fig; 8 is a vertical sectional view on the line 8-8 of Fig. 3;

Fig. 9 is a detail perspectiveview of the looper hooks and carriertherefor;

Fig. 10 is a vertical sectional view on the line Ill-ll] of Fig. 3; I

Figs. 11 and 12 are detail views showing the looper hooks in endelevation, and illustrating the rocking motion of those members;

Fig. 13 is a diagrammatic view illustrating the contour of the camsurface by which the looper carrier is reciprocated in its mounting;

Fig. 14 is a similar view of the cam by which the looper carrier isrocked;

Fig. 23 is a horizontal sectional View through the loops of two piecesof work to be united and Fig. 24 is an elevational view thereof,illustrating, on an enlarged scale, the stitch produced on the presentmachine; and I I Figs. 25 and 26 are views similar to Figs. 15 and 19,illustrating the functioning of the chain stitch fingers in the absenceof work on the work points. I

The machine disclosed, for the purposes of illustrating the presentinvention, is of the type shown in Patent No. 1,894,885, granted January17, 1933. It is of the type commonly known as a dial looper andcomprises a bed plate 30 mounted on a bracket arm A projecting from abase plate B which may be secured on any suitable support. This bedplate has revolubly mounted thereon the ring 3| in which the impalingpins, or work points, are mounted. The pins 32 are clamped in the ring3! by plates 33 and, while these pins are shown rather widely spaced,this is merely for the purpose of more clearly illustrating theconstruction, it being understood that the invention is more especiallyadapted for the fine-point machine. On the under surface of the ring 3!,there is formed a gear 34 by means of which the ring is revolved on thebed plate by a gear 35 mounted on shaft 36 which also carries a worm.gear 31 meshing with a worm I38 on a stub shaft 39. Shaft 39 alsocarries a gear 38 meshing with a gear 40 on a shaft 4! and this shaftcarries a gear 42 which meshes with a gear 43 on the drive shaft 44.Power is applied to shaft 44 by a pulley 45 which may be releasablyengaged with the shaft by a clutch mechanism indicated at 46.

As usual, the sewing mechanism comprises two needles 47, 48, adapted tobe advanced through loops of work on the work points 32 from oppositesides of the work and, in view of the fact that the ring 3i carrying thework points is of the continuously rotating type, as distinguished fromthe intermittent operation in some machines, the needles 41, 48, have alateral step-over movement so that they will move in unison with thework points, while engaged with the work loops on the points. Theneedle-actuating mechanism comprises a shaft 49 journaled in suitablebearings on base plate B and carrying a gear 53 in mesh with a gear 5|on shaft 4|. Also mounted on shaft 49 are two cam discs 52, 53, havingcam slots 54 adapted to receive cam rollers 55, 56, journaled on one armof cam levers 57!, 58, respectively. These cam levers 51, 58, arepivoted on a shaft 59. The other arms of cam levers 51, 58, haveattached thereto connecting rods 60, 6|, which, in turn, are attached toneedle arms 62, 63, pivotally and slidably mounted on a shaft 64. Thecontour of the cam slots 54 in the cam discs 52, 53, is such that theneedle arms carrying the needles, 48, will be rocked on shaft 64 toadvance and retract them longitudinally of the work points 32, theneedles being adapted to pass through loops in the work if and when thework is present onthe work points. To impart the laterahstep-overmovement to the needles to move them in unison with the work points,there are mounted on the drive shaft 44 two cam members 65, 66, withwhich cam rollers 57 on rocker arms 68, 59, engage. The rocker arms 68,59, are pivoted on an arm 10 projecting laterally from the bracket A andsaid rocker arms are connected to the hub portions 52 63*, of the needlearms. Thus, the varying contours of cams 65, 66, will, by means ofrocker arms 68, 69, slide or reciprocate the needle arms 62, 63, axiallyof shaft 64, the timing of these sliding movements of the needle armsbeing so related to the advance and retractive motions of the needlearms that the sliding motions will occur at times when the needles arein engagement with the loops of work on the work points.

As will be hereinafter more fully described, the thread of each needleis adapted to be engaged at a time when the needle has advanced andcarried its thread through the work or when the needle is in what istermed its advance position for the purpose of forming in that thread aloop and positioning that loop in the path of the other needle. At thetime this loop is formed in said thread, the other needle is in itsretracted position and is advanced through the loop formed in the needlethread prior to entering the loop of the work on the work points. Forpurposes which will presently appear, this looping of the threads of thetwoneedles is accomplished by looper elements preferably in the form ofhooks H, l2, rigidly mounted on a looper carrier "l3 slidably mounted ina sleeve-like support '14 which is adapted to not only slide in thesupport, but to also be rocked or rotated therein. These sliding androcking motions of the looper carrier are effected by the followinginstrumenarm thereof provided with a .camf'roller 'M en- ,gaging "in the:cam slot of eam member 18 "which is mounted on shaft 4l. 'I heotherwarm :of the (bell crank lever has attached thereto a connectingvrod 19 which is also attached to a roller 80 secured on what might betermed the rear end of 3 carrier "T3 prejecting beyond the 'bearingsleeve 14. As will be apparent, rockingmotionof the bell crank, lever 16will impart a reciprocatory motion to the carrier 13 inits bearing 14.Also i attached to roller 80 on the looper carrier 13 is a 5" connectingrod 8| attached to a lever 82 pivoted on bracket arm andprovided with acam roller 83 working in the cam groove of a cam member 84on shaft 4!.rocking motion of lever fal ei fected by cam '84 is transmitted byconnect- 2 ing rod 8! to the looper carrier 13.: As will here-- inaftermore fully appear, the reciprocatcry mo- @tionof the looper carrier =13is for=-the purpose.

of moving the loop of one thread of one needle intothe path of the otherneedle and the rockingmoticnoftheloopercarrier is for thepurpose ofbringing the loopers into positions at the preper time to engage therespective threads of the two needles; to position the loops of thethreads in the proper vertical planes, sothat they will register'withthe needle that is tob'e projectedtherethrough; and todisengagethelooper 1'3 from the thread at the proper time,

Referring, particularly; to Figs; 15 to 24, wherein the formation of thestitch and a complete i-J cycleof operations of theneedles and loopersin the forming thereof, is illustrated, it will be assumed that needle48. is inits retracted position .withrespect to the loops ofworkindica'ted at 85, l and needle 41 in its advanced. position, ,andthelooper .Il. is shown in position aboutto enga e thread T, and hasadvanced toward needle 48 which has had the step-over movement impartedto it, as indicated by the dotted-arrow line L in Fig. 15. Fig. 17illustrates looper "H as having 51. been moved past needle 48 to-what isits extreme movement toward the right, as viewed "in this figure, duringwhich time it has also been rocked l i to lower the loop into the pathof needle 48, and Wneedle48 is shown partially advanced with its aforward portion projecting through the loop in H slightly in theopposite direction or ,upwardly by the rocking motion of its carrierand'thethread released therefrom. It mightbe stated, for purthismovemenhneedle 41-is being retracted or withdrawn fromthe work loops.shown in 1 6 5% Fig. 18, the loopers have started their retractive 1 Imovement toward the left as viewed in Figs. 17 3, and18, andloopen i2 isabout .to engage the j thr ead T of needle 48 as viewed in Fig. 18. Re-

thread T and is drawing the loop formed therein'towardneedle '41,"which, at this time, has al- N tinostfreached the limit of; itsretractive movetry with, needle 41, the looperhaving been rocked threadT. The loop in thread T having-been thus "caught on theneedle 48, looperH is rocked poses of clarity, that the looper II, in passing needle 48,also engages thread T'pf needle '48,

ferring to Fig. 19, looper 12 has engaged the,

merit. Fig. 20, looper'lfl isshown as having carried the loop in thread?past; butinto registo lower the thread loop somewhat. Needle 41 is alsoshownas having finished its retractive movement and started its advancemovement, having reached a point inits advance movement where its.forwardend has entered the loop in thread T2 Continued advance .ofneedle 41 and continuedretraction of needle 48 is illustrated in Fig. 21and, :as will also be noted in this figure,

the direction .of movement of the loopers H, 12, has again beenreversed,so that the threads of the .needles will be entirely free oflooper l2 and these movements continue as indicated in Fig. 22, whereinthe several parts are shown as approaching the positions in which theyare illustrated in Fig. 15, thus completing the cycle of operationsperformed in the formation of the present stitch.

It is not deemed necessary to describe, in detail, the threading-up .ofthe sewing mechanism but, as will be appreciated, the tensioning of thethreads T, '1" is such that the loopers H, 12, can readily withdraw thethread from the needles during the formation and proper positioning ofthesuccessive loops. Thus, no strain is imposed upon the needle itself.and, as a consequence, a comparatively small or fine needle, whichwould ordinarily flex very readily, can be used in the present machine,with the result that the present machine is highly. adapted for work ofexceedingly fine mesh.

"The cycle of operations just described is assumed to have beenperformed in connection with loops 8501 work present on the work points,under which circumstances the :loops formed in the thread T of needle41, when the latter is advanced, cannot be withdrawn duringretractionofthesneedle by reason of the fact that it is impaled onneedle 48 and thread T is held in proper position by its needle and theloops of work to position it in the path of looper l2. HoweverQinthew-absence of work on the work points, .these conditions would notprevail and the machine .could not successfully form the stitches. Asaconsequence, :it is necessary that there be provided means forpermitting the needles to properly form stitches in the absence of:"work .on the work points, as this condition actually exists in thenormal .use of the machine byjreason hi the spacing of successive piecesof work on the circular serieszof work points. This continued formationof stitches in the absence of work is known in the artias the forming ofa chain stitch because the successive stitches makeup what has theappearance of a chain. In ,the present instance, this chain stitchdevice cp nprisestwo thread-engaging elements, which might beconveniently termed fingers, which are best seen in Figs. 2, 3 and '7.These fingers indi cated at 86, 81, are secured by screws 88 to abracket .89 mounted on the ,guard 90 which is usually provided for thepurpose .of assuring retention of the workloops on thework points asthey are brought .into operative relationship with the sewing mechanism.These fingers have their free extremities offset downwardly at a pointintermediate the two needles 41, 48, and said down-turned portions arepreferably of hook formation, in that their opposed edges 9| areconcaveand their exterior edges 92 convex. Re-

8'6." Thisconditionis alsotrue of the illustration last loops of a pieceof work have passed the sewing needles and the machine has startedchaining off. Under these conditions, it will be impossible for thatportion of thread T constituting the last-formed loop in saidthread tobe withdrawn by the thread-tensioning mechanisms or for said loop insaid thread to be drawn to ward or into the path of needle 41, asindicated in dotted lines in Fig. 25. In other words, if the loop inthread T was not held by stitch finger 86, that loop would be free to bepulled toward needle 41, as viewed in Fig. 25, to a point where it wouldfoul the needle and possibly be picked up by the looper in the nextcycle of operations. Stitch finger 8? is on the opposite side of thevertical plane in which the work loops are normally supported on thework points and, in the absence of work on said points, this finger willreceive, on its hooked inner face, the thread T, when needle 48 isadvanced, as shown in Fig. 26. The thread 'I" being engagedby the hookoffinger 81 insures the portion of the thread lying. between said fingerand. the eye of needle .48 being retained in position to be engaged bythe looper for the purpose of forming a loop therein in the absence ofwork on the work points. Finger 8! also holds the thread T at a pointcircumferentially in advance of needle 41. In other words, the presenceof finger 81 causes the loop in thread '1" to be formed between saidfinger 81 and the eye of the needle. In the absence of finger 81, and inthe absence of work on the Work points, it will be impossible for thisloop to be formed in thread T. It should be mentioned that, in thenormal operation of the machine, i. e., with work on the work points,the work loops hold thread T depressed, so that said thread will passunder stitch finger 81, as illustrated in Figs. 19 and 20. It will alsobe appreciated that, in the absence of work and in the absence of stitchfinger 81, there would be nothing to anchor the thread T at a point farenough in advance of needle 47 to properly form the loop therein. Itisfor this reason that it has previously been stated that no loop couldbe formed in the absenceof work on the work points if the stitch fingerell was not present.

Thus, the machine is capable of continuously producing properly formedstitches regardless of whether or not loops of work are on the workpoints. At the same time, this chaining off operation does not requirethe presenceof the socalled jacks between successive work points in theseries of work points, so that extremely fine or narrow points with aminimum space between them can be used for operating on fabrics ofexceeding small or fine mesh.

What I claim is:

1. In a sewing machine comprising a series of spaced work-supportingpoints, the combination of a pair of sewing needles movable through workon said points from opposite sides of the work, a reciprocatory rod, andmeans on said rod movable transversely of said needles and engageablewith threads carriedby the needles to form a loop in said threads andposition each loop formed in the threadof one needle in the path of theother needle.

threadcarr'ying needles movable through the work from opposite sidesthereof, a pair of hook members, and. a member on which both of said,

of Figs. 25 and 26, whereinitwill be noted the hooks are mounted, saidmember beingmovable to carry each hook transversely of the paths of saidneedles from a point adjacent one needle to a point adjacent theotherneedle in planes to engage the thread of the said one needle andposition a loop of said thread in the path of the said other needle.

3. In a sewing machine comprising a series of spaced work-receivingpoints, the combination of a pair of thread needles, means for advancingand retracting said needles through the work from opposite sidesthereof, a slidable member,

meansfor reciprocating said member, means on said member engageable withthe threads of said needles to form loops therein and movable toposition the loops formed in the thread of each needle in registry withthe other needle, and means for rocking said slidable member tofacilitate release of the thread loops from said loopforming means. a

4. In a sewing machine comprising a series of work-receiving points, adrive shaft, a pair of thread needles and means operable by said shaftfor advancing and retracting said needles through the work from oppositesides thereof, the combination of a looper element for each needle, asupporting member for said looper elements, and means operable by saiddrive shaft for rocking said supporting member and axially reciprocatingsaid member.

5. In a sewing. machine comprising a series of work-receiving points, adrive shaft, a pair of thread needles and means operable by said shaftfor advancing and retracting said needles through the Work from oppositesides thereof, the combination of a looper hook for each needle, asupport in which both said hooks are rigidly mount 'ed, and meansoperable from said drive shaft for 1 accommodate the edges of Workmaterial between them.

7. A looper mechanism for sewing machines comprising a carrier,amounting in which said carrier is supported, said carrier being rotatabe and slidable longitudinally of its axis of rotation, and a pair oflooper members mounted on the carrier said looper members being spacedapart transversely of their carrier to accommodate the edges of workmaterial between them.

8. In a sewing machine comprising a series of spaced work-supportingpoints, a pair of thread needles movable through Work on the points fromopposite sides of the work and looper elements for looping the thread ofeach needle around the other needle, the combination of a stitch fingerfor one needle positioned to engage and temporarily retain the loopformed in the thread of its needle in the absence of work on said workpoints and a second stitch finger engageable with the thread of theother needle to position said thread in the path of the looper for saidother needle in the absence of work on the work points.

9. In a sewing machine comprising a series of spaced work-supportingpoints, a pair of thread needles movable through work on-the points fromopposite sides of the work and looper elements for looping the thread ofeach needle around the in the path of the looper for the other needle inthe absence of work on the work points.

10. In a sewing machine comprising a series of spaced work-supportingpoints, a pair of thread needles movable through work on the points fromopposite sides of the work and looper elements for looping the thread ofeach needle around the other needle, the combination of laterally spacedmembers positioned above the work points in fixed relation thereto, oneof said members being engageable in the loop formed in the thread of oneneedle and the other member being engageable with the thread of theother needle to position the thread of said other needle in the looperfor that needle in the absence of work on the work points.

on the work points, one of said fixed members 35 I path of theloop-forming means of said other needle.

onslymoving series of work-supporting points, a

pair of thread needles movable in opposite directionslrlongitudinally ofsaid points, and looper 1 1 members for forming loops in the threads ofsaid needles, the combination of fixed members posi- *tioned between thetwo needles in a plane to 11. In a sewing machine comprising acontinuously moving series of work points, a pair of sewing needles,means for advancing and retracting said needlesthrough work on saidpoints from opposite sides of the work, and means for forming a loop inthe thread of each needle while the needle is in its advanced position,the combination of fixed members engageable with the threads of saidneedles in the absence of work engaging the loop formed in the thread ofone needle and the other member engaging the thread of the other needleto position said thread in the 12. Ina sewing machine comprising acontinutions longitudinally of said points, and looper 7 members forforming loops in the threads of the needles, the combination ofoppositely disposed hook-shaped fingers positioned in planes to en gagethe threads of the respective needles to restrain movement of thethreads longitudinally of the work points during the movement of thethread needles longitudinally of the points in the absence of work onthe work points.

14. In a sewing machine comprising a continuously movingseries ofwork-supporting points,.a pair of thread needles movable in oppositedirections longitudinally of said points, and looper members for formingloops in the threads of the needles, the combination of means forlimiting movement of the threads longitudinally of the work points inthe absence of work on the work points, said means comprising twoopposite fingers spacedfrom each other longitudinally of the workpoints, said fingers being mounted in fixed position above the workpoints with portions thereof oifset and projecting downwardly into theplane in which the threads are normally moved by the thread needles.

15. In a sewing machine comprising a series of spaced work receivingpoints, the combination of a pair of thread needles,- means foradvancing and retracting said needles through the work from oppositesides thereof, a member slidable transversely of the path of saidneedles, means for reciprocating said member, and means on said memberengageable with the threads of said needles to form loops in saidthreads, said member being movable to position the loops in the threadof each needle in registry with the other needle.

THOMAS H. DE SPAIN.

